Monday
Monday: The Ocean Moves Heat
Rocket drags a beach ball painted like Earth up to Station Rooftop. Most of it is blue.
"Seven tenths of this planet is ocean," he says. "So the ocean must be running the weather."
Raven spins the ball slowly and watches the blue bands roll by. "What do you notice about where the Sun hits hardest?"
Rocket points at the middle. "The tropics get the direct beam. The poles get a slant."
Nova hovers over the ball and glows along the wide blue stretches. "Then where does all that tropical heat go?" she asks. "Does it just stay put?"
Rocket frowns at the painted waves. "It moves," he says slowly. "The water moves it."
"Then this week we follow the water," Raven says.
A planet mostly covered in water
The ocean covers about 70 percent of Earth's surface. That makes it a huge part of how the planet works.
NASA explains that the ocean takes in heat from sunlight and then moves that heat around the planet.
Sunlight is not spread evenly. Because Earth is a sphere, the tropics get more direct sunlight than the poles.
Ocean currents carry heat away from the tropics and toward cooler places. This makes the planet's heat more even than it would be.
Water is excellent at storing heat. It can take in a lot of heat before it starts to feel warm.
Air is not nearly as good at this. NASA notes that the top few meters of the ocean store as much heat as Earth's entire atmosphere.
You saw this in week 2 when your cup of soil warmed faster than your cup of water.
So the ocean warms slowly, cools slowly and gives its heat back over a long time. That steady heat shapes the climate of every coast.
- Read the question.
- Tap your answer.
| Statement | True or false? |
|---|---|
| Water can take in a lot of heat before it feels warm. | ? |
| Air stores heat better than water does. | ? |
| The top few meters of the ocean store as much heat as the whole atmosphere. | ? |
| The ocean warms and cools quickly, like soil. | ? |
Weather, climate and climate zones
Weather is what you see outside today. Climate is the average of that weather over a long time.
NOAA puts it this way: climate is what you expect, weather is what you get.
The climate where you live is called regional climate. It is the average weather of a place over more than thirty years.
Regional climate depends on four things. They are the amount of sunlight, the height above sea level, the shape of the land and closeness to the ocean.
This week you will test each of those factors with real data from four cities.
Heat on the move
Think of the ocean as a slow delivery system. Warm water leaves the tropics at the surface and travels toward the poles.
As it travels, it gives heat to the air above it. Winds then carry that warmer air over nearby land.
Cold water travels back toward the tropics deep below the surface. You will trace that loop on Tuesday.
NGSS asks you to build a model of this. Your model this week will be drawings, a jar of water and a table of real numbers.
- Read the question.
- Tap your answer.
Put a finger on the widest stretch of ocean you can find. Which continents does it touch?
The lessons never ask where your family lives. If your student wants local normals, you can look them up together on weather.gov.
Strong start. Tomorrow you learn what makes the water move in the first place.